EP0384603A1 - Procédé de production d'oxyde de magnésium - Google Patents

Procédé de production d'oxyde de magnésium Download PDF

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Publication number
EP0384603A1
EP0384603A1 EP90301158A EP90301158A EP0384603A1 EP 0384603 A1 EP0384603 A1 EP 0384603A1 EP 90301158 A EP90301158 A EP 90301158A EP 90301158 A EP90301158 A EP 90301158A EP 0384603 A1 EP0384603 A1 EP 0384603A1
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Prior art keywords
magnesium oxide
magnesium
particle diameter
particles
water
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EP90301158A
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German (de)
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EP0384603B1 (fr
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Shigeo Miyata
Hitoshi Anabuki
Hitoshi Manabe
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Kyowa Chemical Industry Co Ltd
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Kyowa Chemical Industry Co Ltd
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    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
    • C01F5/00—Compounds of magnesium
    • C01F5/02—Magnesia
    • C01F5/06—Magnesia by thermal decomposition of magnesium compounds
    • C01F5/08—Magnesia by thermal decomposition of magnesium compounds by calcining magnesium hydroxide
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
    • C01F5/00—Compounds of magnesium
    • C01F5/02—Magnesia
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
    • C01F5/00—Compounds of magnesium
    • C01F5/14—Magnesium hydroxide
    • C01F5/22—Magnesium hydroxide from magnesium compounds with alkali hydroxides or alkaline- earth oxides or hydroxides
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09C—TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES ; PREPARATION OF CARBON BLACK  ; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS
    • C09C1/00—Treatment of specific inorganic materials other than fibrous fillers; Preparation of carbon black
    • C09C1/02—Compounds of alkaline earth metals or magnesium
    • C09C1/028—Compounds containing only magnesium as metal
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B3/00—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties
    • H01B3/02—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of inorganic substances
    • H01B3/10—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of inorganic substances metallic oxides
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2002/00—Crystal-structural characteristics
    • C01P2002/60—Compounds characterised by their crystallite size
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/60—Particles characterised by their size
    • C01P2004/61—Micrometer sized, i.e. from 1-100 micrometer
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2006/00—Physical properties of inorganic compounds
    • C01P2006/10—Solid density
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2006/00—Physical properties of inorganic compounds
    • C01P2006/12—Surface area

Definitions

  • the present invention relates to a process for the production of a magnesium oxide having high hydrolysis resistance and high fluidity.
  • the present invention relates to a process for the production of a magnesium oxide useful in a thermal conductivity improver of a resin, heat resistant material, electricity insulating material, sheathed heater filler, optical material, polishing material, etc., which has not only physical properties inherent to magnesium oxide such as high melting point (about 2,800°C), high electric insulation quality, low dielectric loss characteristics, high light permeability, high thermal conductivity, basicity, etc., but is also imparted with high hydrolysis resistance and high fluidity.
  • Mangesium oxides are classified into light burnt magnesium oxide (about 600 to 900°C) and hard burnt magnesium oxide (about 1,100 to 1,500°C).
  • the former utilizes the excellent chemical activity which magnesium oxide exhibits in the neutralization of acids and halogens, and one typical example of such use is an acid acceptor for halogenated rubbers such as chloroprene, Hypalon, etc.
  • the latter is used in articles which take advantage of the excellent physical properties of magnesium oxide, i.e.
  • high melting point about 2,800°C
  • high electric insulation quality at high temperature light permeability over a wide wavelength range
  • high thermal conductivity, etc. such as a heat resistant container, heat resistat part, heat insulating material, IC substrate, lens, sodium lamp container, sheathed heater, filler for resins, etc., polishing material, and the like.
  • magnesium oxide has a problem that it is gradually corroded with water or steam and converted to magnesium hydroxide (hydration) whereby its various physical properties explained above are lost, and the scope of its use is hence limited.
  • Japanese Laid-­Open Patent Publication No. 85474/1986 proposes a firing process carried out at a temperature of not less than 1,600°C and below a melting temperature (2,800°C). Further, Japanese Laid-Open Patent Publication No. 36119/1986 proposes a process which comprises reacting a water solution containing a water-­soluble magnesium salt with ammonia in such an amount that is 1 to 3.5 equivalent weight based on 1 equivalent weight of magnesium in the presence of a seed of magnesium hydroxide, thereby to form a magnesium hydroxide of an apparently spherical aggregate having an average secondary particle diameter of 5 to 500 ⁇ m, and firing the aggregate at 1,200 to 2,000°C.
  • Japanese Laid-Open Patent Publications Nos. 288114/1987 and 45117/1988 propose processes which comprise subjecting a fine powder of magnesium oxide to surface treatment with an organic silicate compound, and then subjecting the fine powder to heat treatment to form coatings of silica on the particle surfaces of the magnesium oxide.
  • a magnesium oxide which is formed by reacting an aqueous solution of a water-soluble magnesium salt with a prescribed amount of ammonia in the presence of a seed of magnesium hydroxide and then firing the reaction product at 1,200 to 2,000°C, has improved fluidity and can be easily filled into resins as compared with a powder-form product.
  • the powder-form product here stands for a powder of coarse (not spherical) particles having an average particle diameter of about 10 to not more than 20 ⁇ m and nonuniform profiles, which are obtained by mechanical pulverization.
  • the magnesium hydroxide before the firing has a relatively large crystal form and has a fish scale-like profile, the formability by firing is not satisfactory, although it is improved more than that of a powder of magnesium hydroxide. Further, this magnesium hydroxide has to be fired at higher temperature. And, not only particles bond to each other in an aggreate, but also aggreates bond to each other, and there is an necessity of pulverization with high strength. As a result, nearly spherical secondary aggregates are concurrently destroyed, and the defect portion on the crystal surface increases in size. There is therefore formed a magnesium oxide having insufficient resistance to hydrolysis.
  • the process which comprises subjecting a fine powder of magnesium oxide to surface treatment with an organic silicate compound, and then subjecting the fine powder to heat treatment to form coatings of silica on the particle surfaces of the magnesium oxide, there is provided a surface-­coated magnesium oxide of which the hydrolysis resistance per unit area is improved as compared with magnesium oxide per se, since the surface of the magnesium oxide is coated with silica. Since, however, the surface area is large, the hydrolysis resistance is insufficient, and a larger amount of an organic silane is required due to large surface areas of about 5 to 20 m2/g. Therefore, this surface-coated magnesium oxide is not economical, and there is also a problem that the excellent thermal conductivity of magnesium oxide is deteriorated.
  • the object of the present invention is to solve the above problems and provide a process for the production, at a firing temperature lower than those used in conventional processes, of a magnesium oxide which not only has high fluidity to permit excellent workability, but also has a secondary particle diameter and bulk density to enable high-­filling of itself into a resin required for sufficient improvement of thermal conductivity, and which further has high resistance to hydrolysis.
  • Another object of the present invention is to provide a process for the production of a magnesium oxide which comprises treating the above magnesium oxide having high hydrolysis resistance with an organic silane, whereby the magnesium oxide is imparted with excellent hydrolysis resistance.
  • a process for the production of a magnesium oxide which comprises bringing the magnesium oxide obtained in the above process into contact with a mixture liquid of alkoxysilane, alcohol, water and acid, and then firing the treated magnesium oxide at 500 to 900°C to form a Silicon oxide on the surface thereof.
  • the magnesium oxide obtained according to this process also has high fluidity and high filling ability.
  • the present invention has been completed by the following finding, that is, a magnesium oxide having high fluidity, high filling ability and high hydrolysis resistance can be obtained by forming, at first, a high-dispersibility crystallite magnesium hydroxide synthesized in special methods of the above steps (A) and (B) into particles by using a spray drier at the above step (C), and then subjecting the particles to the low temperature firing at the above step (D) and the pulverization under conditions which do not substantially destroy the fired particles at the above step (E).
  • the synthesis of the high-dispersibility crystallite magnesium hydroxide in the above steps (A) and (B) is carried out by mixing and reacting a water-soluble magnesium salt with an alkaline substance in an amount of not more than 0.95 equivalent weight, preferably 0.5 to 0.90 equivalent weight, based on 1 equivalent weight of the water-soluble magnesium salt, at a temperature of not more than 40°C, preferably not more than 30°C, and then heating the reaction product together with its reaction mother liquor at about 50 to 120°C under atmospheric or elevated pressure for about 0.5 to several hours.
  • a magnesium hydroxide which is a high-dispersibility cryatllite having an average secondary particle diameter of not more than 2 ⁇ m, a BET specific surface area of 15 to 60 m2/g, a plate-like cryatal diameter of about 0.01 to 0.5 ⁇ m and a thickness of 0.01 to 0.1 ⁇ m.
  • a particularly preferable magnesium hydroxide can be obtained, which has an average secondary particle diameter of not more than 1.0 ⁇ m, a BET specific surface area of 20 to 40 m2/g, a plate-like crystal diameter of 0.05 to 0.3 ⁇ m and a plate-like crystal thickness of 0.02 to 0.06 ⁇ m.
  • Examples of the water-soluble magnesium salt used in the above step (A) are magnesium chloride, magnesium nitrate, magnesium acetate, etc.
  • Examples of the alkaline substance are sodium hydroxide, calcium hydroxide, potassium hydroxide, ammonia, etc.
  • the formation of particles by using a drier in the step (C) is carried out by, first, washing the magnesium hydroxide obtained in the above step (B) with water to remove impurities, and then forming the magnesium hydroxide into particles in the presence or absence of a binder and drying them, Where it is freely possible to form generally spherical particles having an average secondary particle diameter in the range of from about 5 to 500 ⁇ m. Incorporation of the binder is preferable in view of the fact that it increases the strength of the formed particles and prevents the sintering among the particles at the firing time.
  • the particles obtained as above are composed of a magnesium hydroxide having high fluidity and high sinterability.
  • binder examples include organic binders such as polyvinyl alcohol, carboxymethyl cellulose, polyethylene wax, polyacrylic acid, polyvinyl acetate, styrene-acryl copolymer, gum arabic, polystyrene, sodium alginate, etc.
  • organic binders such as polyvinyl alcohol, carboxymethyl cellulose, polyethylene wax, polyacrylic acid, polyvinyl acetate, styrene-acryl copolymer, gum arabic, polystyrene, sodium alginate, etc.
  • the firing of the magnesium hydroxide at the step (D) is carried out at a temperature of about 1,100 to 1,600, preferably about 1,200 to 1,400°C for about 0.5 to several hours under natural atmosphere or atmospher of oxygen, nitrogen, etc., by using a firing apparatus such as a rotary kiln, tunnel furnace, muffle furnace, etc. If the firing temperature is lower than the above lower limit, the resultant magnesium oxide has insufficient hydrolysis resistance, and when it is higher than 1,400°C, the resultant product is too hard and required to be pulverized with high strength, with the result that the spherical partricle forms thereof are damaged to deteriorate its fluidity. Further, the hydrolysis resistance of the product is hardly improved as compared with that of a product formed by firing at lower temperatures than said upper limit.
  • the pulverization of the fired product at the step (E) is carried out by using a ball mill, crusher, etc., for about dozens of minutes to several hours until the product is pulverized to a size of the particles formed at the step (C).
  • the pulverization is performed for such a period of time that the particles obtained at the step (C) are not substantially destroyed.
  • the firing temperature is suitably selected, it is possible to obtain as soft a fired product as can be also pulverized to the size of the particles only by using, e.g. a screen classifier without using any of the above pulverizing means.
  • steps (A) to (D) of the present invention are carried out, i.e., only when the magnesium oxide is formed by subjecting the high-­dispersibility crystallite magnesium hydroxide produced at the step (B) to the particle formation and drying using a spray drier at the step (C) and then firing the formed particles at a low temperature at the step (D), it is possible to maintain the spherical forms in the pulverization of the step (E).
  • the magnesium oxide formed in the step (D) of the present invention is in a state that the sintering has proceeded only within each of the spray-formed particles, and the magnesium oxide can be easily pulverized and exhibits hydrolysis resistance at high level.
  • the magnesium oxide pulverized in the step (E) has a nearly spherical form, a secondary particle diameter of about 5 to 500 ⁇ m, preferably about 10 to 50 ⁇ m and a bulk density of not less than about 1 g/ml. Due to these properties, this magnesium oxide can be incorporated into a resin in such an amount that is necessary to impart the resin with sufficient thermal conductivity, and has excellent workability for forming ceramics. Individual single crystals within the fired and pulverized product have a particle diameter of about 0.5 to 10 ⁇ m and a BET specific surface area of not more than 1 m2/g.
  • the magnesium oxide obtained as above can be further imparted with hydrolysis resistance at higher level by treating it as follows.
  • the magnesium oxide is brought into contact, by mixing, with a mixture liquid of an alcohol such as methyl alchol, ethyl alcohol, etc., an alkoxy siliane such as methoxy silane, ethoxy silane, etc., a small amount of water, and an acid such as hydrochloric acid, nitric acid, phosphoric acid, surfuric acid, etc., at a temperature up to about 100°C, and the magnesium oxide is then separated by means of filtration, etc., and fired at a temperature of about 300 to 900°C, preferably about 500 to 800°C for about 0.1 hour to several hours.
  • an alcohol such as methyl alchol, ethyl alcohol, etc.
  • an alkoxy siliane such as methoxy silane, ethoxy silane, etc.
  • an acid such as hydrochloric acid, nitric acid, phosphoric acid, surf
  • the magnesium oxide obtained as above has further improved hydrolysis resistance, since the surface of magnesium oxide crystals exposed on the surface of the fired and pulverized product obtained at the step (E) is coated with silica or a reaction product between silica and magnesium oxide.
  • the amount of the alkoxysilane, as SiO2, for the above coating is about 0.1 to 3 % by weight, preferably about 0.2 to 2.0 % by weight, based on the magnesium oxide.
  • those individual single crystals within the fired and pulverized product that have surface coatings of the alkoxysilane have a BET specific surface area of not more than 1 m2/g. Therefore, not only high hydrolysis resistance can be achieved by using a smaller amount of silica than that in a conventional technique for coating a magnesium oxide powder with silica, but also the required amount of silica can be decreased. As a result, the excellent physical properties inherent to magnesium oxide, such as thermal conductivity, etc., are not deteriorated.
  • the copresence of a small amount of water and an acid is useful to promote the reactivity of the alkoxysilane to the magnesium oxide surface.
  • angles of repose were measured by using an angle of repose measuring device (model FK) manufactured by Konishi Seisakusho.
  • Ion bittern (20 l) containing 1.5 moles/l of magnesium chloride and 0.5 mole/l of calcium chloride was charged to a 50-liter stainless steel cylindrical reactor with a stirrer, and the temperature thereof was adjusted to about 25°C by using a jacket.
  • 12 l of sodium hydroxide (4.0 moles/l, corresponding to 0.8 equivalent weight based on magnesium chloride) was all added over about 5 minutes while the mixture was stirred, and the reaction mixture was further stirred for 5 minutes. Then, the temperature thereof was elevated up to 90°C with stirring, and maintained at this temperature for about 2 hours. Thereafter, the reaction mixture was dehydrated by filtration under reduced pressure and washed with water to give a magnesium hydroxide.
  • the magnesium hydroxide had a BET specific surface area of 22 m2/g and an average secondary particle diameter, measured by microtrack method, of 0.53 ⁇ m, and contained 99.6 % by weight of Mg(OH)2 and 0.02 % by weight of CaO.
  • the above magnesium hydroxide was dispersed in water to form a slurry containing about 20 % by weight thereof. 1 % by weight, based on the magnesium hydroxide, of a polyethylene wax in an emulsion state was added to and uniformly mixed with the slurry. Then, the mixture was formed into particles by using an NIRO spray drier in which the hot air inlet temperature was about 350 to 370°C and the air outlet temperature was about 100 to 110°C according to an atomizer method.
  • the scanning electron microscopic observation of the formed particle showed that the magnesium hydroxide had nearly truly spherical profiles having a diameter of 20 to 40 ⁇ m, a cryatal length of 0.1 to 0.2 ⁇ m, a thickness of 0.02 to 0.04 ⁇ m (magnification, 1,750 diameters in Fig. 1, 10,000 diameters in Fig. 2).
  • This spray-dried magnesium hydroxide was separated into three portions, and these portions were fired in a kanthal furnace at 1,150°C, 1,250°C and 1,400°C for 2 hours, respectively.
  • the fired products obtained by firing at 1,150°C and 1,250°C were so soft as to be hand-crushable.
  • the fired products each were pulverized in a ball mill for 0.5 to 1 hour, and the average secondary particle diameter of each was measured by a microtrack method to show about 22 ⁇ m.
  • the scanning electron microscopic observation showed that the fired products each were a sintered body in which nearly truly spherical crystals of magnesium oxide were densely filled (Fig. 3, magnification, 1,000 diameters).
  • Table 1 shows the physical properties of the products fired at 1,150°C, 1,250°C and 1,400°C.
  • Firing temperature Crystal particle diameter BET specific surface area Apparent specific gravity °C ⁇ m m2/g g/ml 1,150 2-3 0.5 1.1 1,250 3-6 0.2 1.2 1,400 6-10 0.1 1.5
  • TABLE 1 (continued) Firing temperature Hydrolysis resistance Angle of repose MgO content °C wt.% wt.% 1,150 6.4 44° 99.4 1,250 5.1 44° 99.5 1,400 3.6 44° 99.8
  • Part of the magnesium hydroxide obtained in Example 1 was mixed with a styrene/acryl copolymer as a binder in an amount of 2 % by weight on the basis of the magnesium hydroxide, and the mixture was formed into particles and dried by using a nozzle type spray drier (manufactured by NIRO) having a nozzle diameter of 2.4 mm under the adjustment of the hot air inlet temperature 400 to 420°C and the air outlet temperature to 150 to 170°C.
  • a nozzle type spray drier manufactured by NIRO
  • the optical microscopic observation of the resultant magnesium hydroxide showed that it was spherical particles having a diameter of about 100 to 300 ⁇ m.
  • magnesium hydroxide particles were fired at 1,250°C for 3 hours.
  • the fired particles were so soft as to be hand-crushable.
  • These particles were treated in a ball mill for 30 minutes to give a magnesium sintered body having a nearly truly spherical form with an average secondary diameter of about 200 ⁇ m.
  • Table 2 shows physical properties of the sintered body.
  • each of the magnesium oxides (a product fired at 1,150°C, 1,250°C or 1,400°C in Example 1) was added to a mixture liquid of 3.5 g of tetraethoxysilane, 250 ml of ethyl alcohol, 20 ml of water and 20 ml of hydrochloric acid, and the mixture was fully stirred at about 70°C for 5 minutes, and filtered. The remaining solid was heated at 800°C for 2 hours to give a silane-treated magnesium oxide.
  • Table 3 shows physical properties of the silane-­treated magnesium oxides. TABLE 3 Products fired at Hydrolysis resistance SiO2 content MgO content °C wt.% wt.% wt.% 1,150 0.87 0.74 99.0 1,250 0.79 0.72 99.1 1,400 0.36 0.71 99.2
  • a magnesium hydroxide powder having a BET specific surface area of 40 m2/g and a secondary average particle diameter of 4.8 ⁇ m was fired in a kanthal furnace at 1,400°C for 2 hours, and then pulverized in a ball mill for about 6 hours.
  • the resultant fired product showed a hydrolysis resistance value of 28 wt.% and a angle of repose of 59°.
  • This magesium oxide was treated with silica in the same way as in Example 2, and the silica-treated product had a hydrolysis resistance value of 15.2 wt.%.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)
EP90301158A 1989-02-10 1990-02-05 Procédé de production d'oxyde de magnésium Expired - Lifetime EP0384603B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP1031592A JP2731854B2 (ja) 1989-02-10 1989-02-10 高耐水和性、高流動性酸化マグネシウムの製造方法
JP31592/89 1989-02-10

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EP0384603A1 true EP0384603A1 (fr) 1990-08-29
EP0384603B1 EP0384603B1 (fr) 1995-01-18

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US (1) US5039509A (fr)
EP (1) EP0384603B1 (fr)
JP (1) JP2731854B2 (fr)
CA (1) CA2009715C (fr)
DE (1) DE69016057T2 (fr)
ES (1) ES2069679T3 (fr)

Cited By (7)

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WO1992012097A1 (fr) * 1990-12-26 1992-07-23 The Dow Chemical Company Hydroxyde de magnesium de structure cristalline en couches superposees et procede de production
EP0780425A1 (fr) * 1995-12-19 1997-06-25 Kyowa Chemical Industry Co., Ltd. Ignifugeant avec bonne résistance à la détérioration par la chaleur, composition de résine et articles moulés
US6025424A (en) * 1995-12-19 2000-02-15 Kyowa Chemical Industry Co Ltd Heat deterioration resistant flame retardant, resin composition and molded articles
EP1153984A1 (fr) * 1999-11-22 2001-11-14 Kyowa Chemical Industry Co., Ltd. Composition de resine, article moule fabrique a partir de ladite resine et utilisation associee
EP1818311A1 (fr) * 2004-12-01 2007-08-15 Tateho Chemical Industries Co., Ltd. Poudre d'oxyde de magnesium a enrobage contenant du phosphore, son procede de production et composition de resine la contenant
WO2007093258A2 (fr) * 2006-02-14 2007-08-23 Merck Patent Gmbh Magnesie poreuse et son procede de preparation
US9724302B2 (en) 2010-04-09 2017-08-08 Pacira Pharmaceuticals, Inc. Method for formulating large diameter synthetic membrane vesicles

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US5569684A (en) * 1994-03-03 1996-10-29 Takita Patent & Engineering Heat conductive silicone rubber composition
US6179897B1 (en) 1999-03-18 2001-01-30 Brookhaven Science Associates Method for the generation of variable density metal vapors which bypasses the liquidus phase
KR20000049740A (ko) * 2000-04-26 2000-08-05 김철우 분무배소법에 의한 마그네시아 분말의 제조방법
US6387993B1 (en) * 2000-06-05 2002-05-14 H. B. Fuller Licensing & Financing Inc. Flame retardant composition
JP2003002640A (ja) * 2001-06-18 2003-01-08 Ube Material Industries Ltd マグネシウム含有酸化物粉末、及びその製造方法
EP1421944B1 (fr) * 2001-08-27 2007-12-12 Kyowa Chemical Industry Co., Ltd. COMPRIMES ANTIACIDES ET LAXATIFS COMPRENANT l'OXYDE DE MAGNéSIUM
JP4412879B2 (ja) * 2002-03-11 2010-02-10 メルク株式会社 体質顔料およびその製造方法
WO2005031782A1 (fr) * 2003-09-26 2005-04-07 Pioneer Corporation Ecran d'affichage plasma et son procede de production
AU2003289058A1 (en) * 2003-10-03 2005-04-21 Tateho Chemical Industries Co., Ltd. Coated magnesium oxide powder exhibiting high flowability, and resin composition comprising the powder
JP4237182B2 (ja) * 2003-10-03 2009-03-11 タテホ化学工業株式会社 高充填性被覆酸化マグネシウム粉末及びその粉末を含む樹脂組成物
JP4302690B2 (ja) * 2003-10-03 2009-07-29 タテホ化学工業株式会社 球状被覆酸化マグネシウム粉末及びその製造方法及びその粉末を含む樹脂組成物
JP4650829B2 (ja) * 2005-03-22 2011-03-16 パナソニック株式会社 プラズマディスプレイパネルおよびその製造方法
CN100422084C (zh) * 2005-05-21 2008-10-01 中国科学技术大学 薄片状无孔纳米氧化镁及其制备方法
JP2009515005A (ja) * 2005-11-04 2009-04-09 エルエス ケーブル リミテッド 水酸化マグネシウムポリマーハイブリッド粒子の製造方法
US7771682B2 (en) * 2006-01-31 2010-08-10 Council Of Scientific And Industrial Research Process for the preparation of magnesia (MgO) from crude Mg (OH)2
CN101679058B (zh) * 2007-03-30 2012-11-14 宇部材料工业株式会社 氢氧化镁粉末及其制备方法
JP4926835B2 (ja) * 2007-06-05 2012-05-09 タテホ化学工業株式会社 酸化マグネシウム粉末
JP5125258B2 (ja) * 2007-06-29 2013-01-23 堺化学工業株式会社 球状酸化マグネシウム粒子とその製造方法
US8652248B2 (en) 2008-02-06 2014-02-18 IMI Tami Institute for Research and Development ltd Cement mixes containing additives for altering the hardening rate of chemically bonded silico-phosphate cements and methods therefor
US20110014469A1 (en) * 2009-07-14 2011-01-20 Sakai Chemical Industry Co., Ltd. Magnesium oxide particle, method for producing it, exoergic filler, resin composition, exoergic grease and exoergic coating composition
JP5263076B2 (ja) * 2009-08-25 2013-08-14 新神戸電機株式会社 酸化マグネシウム粉末の製造法、熱硬化性樹脂組成物、プリプレグおよび積層板の製造法
JP5415215B2 (ja) 2009-10-02 2014-02-12 タテホ化学工業株式会社 分散性に優れる酸化マグネシウム粉末及びその製造方法
JP5447355B2 (ja) * 2010-12-02 2014-03-19 新神戸電機株式会社 熱硬化性樹脂組成物の製造法、プリプレグおよび積層板の製造法
EP2707338A4 (fr) * 2011-05-12 2015-01-21 Imi Tami Institute Research Phosphociment à libération lente
CN102433174A (zh) * 2011-10-19 2012-05-02 周志平 一种燃油催化剂及其制备方法和应用
EP2896599A4 (fr) * 2012-09-13 2016-04-27 Kyowa Chem Ind Co Ltd Particules d'oxyde de magnésium en couches minces faiblement agrégées
JP6356435B2 (ja) * 2014-02-28 2018-07-11 神島化学工業株式会社 高耐酸性表面処理酸化マグネシウム系熱伝導剤とそれを用いた樹脂組成物
JP6724332B2 (ja) * 2014-10-31 2020-07-15 堺化学工業株式会社 酸化マグネシウム粒子、その製造方法、放熱性樹脂組成物、放熱性グリース及び放熱性塗料組成物
WO2018180123A1 (fr) * 2017-03-28 2018-10-04 宇部マテリアルズ株式会社 Particule d'oxyde de magnésium revêtue et son procédé de production, et composition de résine thermoconductrice
JP6507214B1 (ja) 2017-12-01 2019-04-24 宇部マテリアルズ株式会社 酸化マグネシウム粉末、その製造方法、熱伝導性樹脂組成物、熱伝導性グリス、及び熱伝導性塗料
JP6652182B2 (ja) * 2018-04-20 2020-02-19 住友電気工業株式会社 樹脂組成物、無機充填剤、直流電力ケーブル、および直流電力ケーブルの製造方法
CN113896216B (zh) * 2021-10-22 2023-06-27 山西银圣科技有限公司 一种重质硅钢级氧化镁的制备方法

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EP0780425A1 (fr) * 1995-12-19 1997-06-25 Kyowa Chemical Industry Co., Ltd. Ignifugeant avec bonne résistance à la détérioration par la chaleur, composition de résine et articles moulés
US6025424A (en) * 1995-12-19 2000-02-15 Kyowa Chemical Industry Co Ltd Heat deterioration resistant flame retardant, resin composition and molded articles
EP1153984A1 (fr) * 1999-11-22 2001-11-14 Kyowa Chemical Industry Co., Ltd. Composition de resine, article moule fabrique a partir de ladite resine et utilisation associee
EP1153984A4 (fr) * 1999-11-22 2002-06-05 Kyowa Chem Ind Co Ltd Composition de resine, article moule fabrique a partir de ladite resine et utilisation associee
US6506828B1 (en) 1999-11-22 2003-01-14 Kyowa Chemical Industry Co., Ltd. Resin composition, molded article therefrom, and utilization thereof
EP1818311A1 (fr) * 2004-12-01 2007-08-15 Tateho Chemical Industries Co., Ltd. Poudre d'oxyde de magnesium a enrobage contenant du phosphore, son procede de production et composition de resine la contenant
EP1818311A4 (fr) * 2004-12-01 2009-07-22 Tateho Kagaku Kogyo Kk Poudre d'oxyde de magnesium a enrobage contenant du phosphore, son procede de production et composition de resine la contenant
WO2007093258A3 (fr) * 2006-02-14 2007-11-01 Merck Patent Gmbh Magnesie poreuse et son procede de preparation
WO2007093258A2 (fr) * 2006-02-14 2007-08-23 Merck Patent Gmbh Magnesie poreuse et son procede de preparation
US9724302B2 (en) 2010-04-09 2017-08-08 Pacira Pharmaceuticals, Inc. Method for formulating large diameter synthetic membrane vesicles
US9730892B2 (en) 2010-04-09 2017-08-15 Pacira Pharmaceuticals, Inc. Method for formulating large diameter synthetic membrane vesicles
US9737482B2 (en) 2010-04-09 2017-08-22 Pacira Pharmaceuticals, Inc. Method for formulating large diameter synthetic membrane vesicles
US9737483B2 (en) 2010-04-09 2017-08-22 Pacira Pharmaceuticals, Inc. Method for formulating large diameter synthetic membrane vesicles
US9757336B2 (en) 2010-04-09 2017-09-12 Pacira Pharmaceuticals, Inc. Method for formulating large diameter synthetic membrane vesicles
US9808424B2 (en) 2010-04-09 2017-11-07 Pacira Pharmaceuticals, Inc. Method for formulating large diameter synthetic membrane vesicles
US10045941B2 (en) 2010-04-09 2018-08-14 Pacira Pharmaceuticals, Inc. Method for formulating large diameter synthetic membrane vesicles
US10398648B2 (en) 2010-04-09 2019-09-03 Pacira Pharmaceuticals, Inc. Method for formulating large diameter synthetic membrane vesicles

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DE69016057D1 (de) 1995-03-02
CA2009715A1 (fr) 1990-08-10
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EP0384603B1 (fr) 1995-01-18
CA2009715C (fr) 1997-09-16
JP2731854B2 (ja) 1998-03-25
US5039509A (en) 1991-08-13
DE69016057T2 (de) 1995-05-18

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